821339223381 has 24 divisors (see below), whose sum is σ = 1197812064384. Its totient is φ = 542301180480.

The previous prime is 821339223379. The next prime is 821339223407. The reversal of 821339223381 is 183322933128.

821339223381 is a `hidden beast` number, since 8 + 2 + 1 + 339 + 2 + 233 + 81 = 666.

It is not a de Polignac number, because 821339223381 - 2¹ = 821339223379 is a prime.

It is a super-2 number, since 2×821339223381² (a number of 25 digits) contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (821339223361) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 241351 + ... + 1304196.

It is an arithmetic number, because the mean of its divisors is an integer number (49908836016).

Almost surely, 2^821339223381 is an apocalyptic number.

It is an amenable number.

821339223381 is a deficient number, since it is larger than the sum of its proper divisors (376472841003).

821339223381 is a wasteful number, since it uses less digits than its factorization.

821339223381 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1546121 (or 1546118 counting only the distinct ones).

The product of its digits is 373248, while the sum is 45.

The spelling of 821339223381 in words is "eight hundred twenty-one billion, three hundred thirty-nine million, two hundred twenty-three thousand, three hundred eighty-one".